In general, it is known to provision telecommunication networks with priority services. For example, the Government Emergency Telecommunication Service (GETS) is employed in the Public Switched Telephone Network (PSTN) to provide priority service to NS/EP (National Security/Emergency Preparedness) personnel. Similarly, WPS (Wireless Priority Service) is employed in cellular or mobile telecommunication networks. Generally, the goal of priority service is to provide a higher probability and/or rate of call completion for selected calls. As is understood in the art, GETS and/or WPS calls receive priority handling as compared to ordinary calls (i.e., non-priority calls).
As can be appreciated, in times of emergency or crisis or otherwise, telecommunication networks can become congested by an unusually heavy call volume. Moreover, natural or other catastrophes may impair or damage network facilities thereby reducing the networks capacity to handle the increased call volume. The unusually high call volume and/or reduced network capacity tends to increase network congestion and limit the network's ability to complete ordinary calls. Services like GETS and WPS and other similar priority services supported by telecommunication networks are employed by users to obtain higher priority for completing calls utilizing these services as compared to ordinary calls.
In order to receive access to a priority service, a user generally subscribes to the particular service or otherwise registers to use the service. To use the service in connection with a particular call, the subscriber typically enters or otherwise submits a password, a user name or number or other ID and/or other authentication credentials at or near the time the call is placed. The submitted credentials are used by the network to verify that the user is in fact a subscriber to the priority service or is otherwise entitled to use the priority service. Provided the supplied credentials are valid, the call associated with the invoked priority service is accepted and generally given priority by the network over ordinary calls, e.g., for purposes of call completion. On the other hand, if the credentials are not valid, then the call is denied as invalid. That is to say, no attempt is made within the network to complete the call.
Customarily, in a Next Generation Network (NGN) (e.g., such as those implementing an Internet Protocol (IP) Multimedia Subsystem (IMS)), a finite amount of network resources are generally allotted or available for handling priority call and/or session requests. Accordingly, a throttling mechanism is commonly employed to limit or otherwise regulate the number of priority call/session requests accepted from a given source and/or handled by a given network node. In particular, a call gapping technique is typically used to achieve the aforementioned throttling when the number of priority call/session requests from a given source, or being handled by a network node responsible for serving that source, exceed a preset value assigned thereto. Conventional call gapping defines periodically reoccurring fixed windows of time or “gaps” during which a limited or otherwise preset number of priority call/session requests are accepted. Once the limit has been reached for a particular gap, no more requests are accepted until the next gap arrives or opens.
While generally acceptable in some circumstances, the foregoing approach to throttling and/or call gapping is unsatisfactory in other respects. For example, one problem with the foregoing implementation is that the preset gapping parameters may not at times accurately reflect the number of priority service subscribers or users at a particular source or accessing a particular node in question. Rather, the preset parameters generally reflect some normal or historical priority service subscriber level at the location or using the node of interest. In many circumstances, the actual level might vary widely from the norm. For example, if there were a convention or meeting of priority service subscribers at a particular location, and during the meeting a crisis developed, the number of priority service call/session requests from that location could vastly exceed the normal or historical level upon which the preset gapping parameters were based. In another example, if there is an emergency incident, priority service subscribers and/or users tend to migrate to the affected area (as would be expected), and again, the number of priority call/session requests from this area or source can vastly exceed the historical norm on which the preset gapping parameters were based. In short, the traditional throttling mechanism described above is at times simply not flexible enough to handle the foregoing situations. Additionally, the foregoing throttling technique does not account for the overall capacity of the serving node nor the degree of invalid requests (i.e., which arrive from individuals without proper credentials). For example, a relatively large number of invalid requests may indicate a potential denial of service attack on the network.
Accordingly, a new and improved system and/or method for dynamically controlling the throttling of priority services calls in a telecommunications network is disclosed that overcomes the above-referenced problems and others.